A Liquid Crystal Display (LCD) device typically controls backlight brightness through dynamic backlight modulation to thereby save energy and improve the display contrast and other image quality-of-picture effects. FIG. 1 is a structural principle diagram of dynamic backlight modulation in the liquid crystal display device in the prior art. The liquid crystal display device includes an image processing component configured to receive an input image signal, and to acquire backlight data as a function of grayscale brightness of the image signal, where on the one hand, the image signal is converted in format according to the predetermined specification of a display panel, and output to a timing controller (Tcon) in a liquid crystal display component, and a timing control signal and a data signal are generated by the timing controller to drive the liquid crystal panel, and on the other hand, the acquired backlight data are output to a backlight processing component, and the backlight data are converted by the backlight processing component into a backlight control signal to control a backlight driver component to control brightness of backlight sources in a backlight assembly so that if the brightness of the image is high, then the backlight source will be driven for high backlight brightness, and if the brightness of the image is low, then the backlight source will be driven for low backlight brightness.